/Engine/Plugins/Runtime/Metasound/Source/MetasoundFrontend/Public/MetasoundFrontendController.h
Add a new input node using the input description.
On success, a valid input node handle. On failure, an invalid node handle.
[FNodeHandle](API\Plugins\MetasoundFrontend\FNodeHandle) AddInputVertex ( const [FMetasoundFrontendClassInput](API\Plugins\MetasoundFrontend\FMetasoundFrontendClassInput) & InDescription )